Tunnel oven



J. DANIELS "Jul 12, 1932.

TUNNEL OVEN Filed March 8, 1930 3 Sheets-Sheet Fi .3(d-d) /n venfon:

July 12, 1932. J. DANIELS 1,866,547

TUNNEL OVEN" Filed March 8, 1930 3 Sheets-Sheet 2 Fig.7 Fig.8 (O -d) (17-6) 07- J. DAN I ELS TUNNEL OVEN July 12, 1932.

Filed March 8, 1930 3 Sheets-Sheet 3 m w m -V W VIIF flu i Ill Patented July 12, 1932 i umjq-en sm -res PATENT OFFI E aosnrnrhmnrs, or. ESSEN-RUHR, GERMANY, AssIeNon, BY MES'NE AssIGNMEiITs, 'ro

- 'rnn'xorrnns COMPANY, on PITTSBURGH, PENNSYLVANIA, A-oo'nPoRArIoN or I DELAWARE "runner. ovnit Application filed March a, 1930,.Serial 110.4342, and in Germany March 9, 1929.

- In connection with tunnel ovens, e. g. ovens used for firing refractory bricks, regenerators for preheating gas and air have been used in order to assist in maintaining a high and even or regularly distributed temperature] in the firing zone, the regenerator extending across or, over the oven chamber. a r

According to my invention the uniformity of heating is increased by ,arranging nu- 10 merous gas and air inlets, alternating with ous sheet of flame is obtained.

each other, side by side along the, oven, in the firing zone, so that a practically continu- For this purpose Ifadopt the known prac tics of placing the regenerators in couples side by side, sothat all the chamber-salong the firing zoneare accessible from the front for cleanin purposes and; repair of I the checker wor iz. I p 1 I may have a series ofregeneratorsof nor mal width individual, communicating at the top with distributing ducts extending lengthwise of the oven, and connect the distributing ducts to discharge ducts leading tothe oven chamber, arranged sothat each pair. of regenerators, heating gas and air respective ly, feeds numerous ducts opening into the oven chamber, the gas inlets alternating with theairinlets. J I I In another modification I use a series of particularly narrow gas and air; heating regenerators; Withthis arrangement I may dispense altogether with a distributing system in the hot, upper part of-theoven, or

may reduce. the same to ducts arranged in,

pairs, two' from each regenerator leading to the oven chamber, and crossed Sothat the series of inlets intothe oven chamber. consists.

of as inlets and air inletsalternating with eac other. This method enables heating with rich gas to be efiected in a very-simple way, the rich gas being iedtotheoven; chamber from outside through the Walls separating the regenerators.-

is Two ,gaXamples of installations according to the invention are shown in -the annexed drawings in Figsal to 3yaI1dFigs. l'to 11* respectively. I e y 4 Fig; 1;is a plan view, ,7 Fig, 2 across-section, and j a Thefdistnbutmg ducts above th regulation for obtaining the desired gradators tQlllB oven chamber. r i 1 Referring first to Figs. 1 to 3, the ,firing zone of-the tunnel oven 10 has a series of re generative gas heaters 11 andregenerative 6.,"

air heaterslil, alternating with each other. For each successive couple of these regenera tors there is a forked supply duct 13, 14. The air and gas preheated in the checker work pass 'out into distributing ducts .15, l6,w hich lie side by side, eachpalr ofthese ducts 1,5, 16 extendingover oneof the couples ofj regenerators 11, 12. Gas ducts 17 17 andair ducts 18,18 leading to the oven chamber alternate withleach other and extend transversely of the. ducts 15, 16, their outlets into the oven forming a continuous series of gas and air orifices alternating with each othen. Dampers 19 are controlled from inspection and service holes 20, for regulating the dischargefrom the several ductslfi'and 16'int0 the ducts 17 and 18 respectively: 7

erators serve as equalizers for thedistribution of gas and air along'the sections of the oven served by the respective. regenerators, that is to say. they Correct irregularities thestreams of gas and air arising from irregularities in the checker-work. Additional tion of temperature is "effected byfmeansolf the dampers. Asthe se ducts in the upper 7 part of the ovenare very hot a substantial transfer of heat to the airand gas takes place therein, so that theregenerators themselves need only be'of moderate height. i Inthe modificatin shownin Figs. 4 to; the alternatingregenerative gas heatersll andair heaters 12- discharge into ducts 18 eadi ig'from the ps hen otto"outletsgpen at? regening into the oven chamberabout midway between the top and bottom levels of that chamber. As shown in Figs. 4 to 7, the regenerators are served in groups of two or more by means of supply ducts 25, but their supplies are separately regulatable by means of dampers 26. This arrangement of regulating dampers has the advantage of being in a coolerpart of the oven, where the gas and air arenot yet pre-heated. v

The distribution of air and gas to the regenerators depends on the gradation of temperature required in the oven. Dampers are provided in the modification also, for additional regulation, so that dead corners in the checker work are largely avoided, whereas such corners are very liable to occur if the air or gas has to flow diagonally throughthe checker-work. The chambers and ducts below the regenerators serve as convenient dust collectors, which can easily be cleaned out by means of discharge ducts having shutters 35, these serving also as vents in case of explosion. The roof bricks of the distributing ducts, which are also the floor bricks of the regenerators, can be taken out to give access to the distributing ducts from openings having shutters 27. A

In order further to reduce the intervals between the air and gas inlets into, the oven,

without making the regenerators unduly narrow, there is provided, between the inlets branches at the upper partsthereof, extending round the ducts 18 and then passingvertically downwards.

Instead of feeding gas and air to the regenerators through the elbow unions 31 shown in Fig. i, the same may be fed in "directly'through the inlets,'regulation of supply being effected at these inlets, The'distributing ducts 25 then serve only for collecting the waste gases and leading them to an elbowunion 31, the waste heat and regenjerator temperature being regulated by means of floor dampers 26. This renders the regulation of inlet and discharge more independent. v

.For compound workinglwith asupply of rich gas 'thewalls dividing the regenerators have fines 32 for this gas, withoutlets 33 in r'ecesses,as shown in Figs. 4: and 8. When changing "over, an air damper 34 is opened, so that the graphite is burnt with fresh air "sucked in fro'm'outside, and'the products of pass directly to the adjacent dividing walls is, very fully'utilize'd for regenerative heating, that is to say more fully than thick walls, which are only heated to a depth of a few centimeters during the usual half-hourly periods of heating up the regen-' erators. The short distances between the walls make for strength of the structure,

so that a tunnel wall thinner than usual can be'used. V

by side instead of regenerators of the usual width, but of course the purpose in that case is not to secure a continuous sheet or strip of flame, but to provide a separate regenerator for each coke-oven chamber, the width of the regenerators depending ultimately on the width of the oven chambers and the thickness of their dividing walls. In that case the regenerator walls'cannot by any means be as thin as with my invention, as they have to bear a heavy load including the charging appliances of the ovens, and in view of the considerable'length' of the oven chambers (say 10 meters or more) the regenerator roof must be strong enough for vehiclesbringing the coal. These conditions do not arise with tunnel ovens, where the sub-division of the re-' generators can be carried to any desired length, and there is no need for vehicles on the roof.

What I claim is: 1

1. A tunnel oven with regenerators for preheating'air and as for combustion distributed along the ring zone, the said regeneratorsfeeding air and gas to air and gas inlets alternating with each other along the tunnel in such a manner that a sheet or strip of flame is produced, regulatable as regards its local intensity. r V

2. Atunnel oven as claimed in claim 1,'hav- 'ing distributing conduits extending lengthwise of the tunnels, communicating with the upper parts of the regenerators and with transversely disposed air and gas feed conduits leading to the alternately disposed air and gas'inlets of the'oven chamber.

3. A tunnel oven with regenerators for preheating air and gas forcombustion-distributed in pairs alongthe firing zone, the said regenerators feeding air and gas to the air and gas inlets alternating with each other along the tunnel firing zone in such manner that a sheet or strip of flame is producedfregulatable as to its local intensity, and in which each pair of consecutive air regenerators-is fed by a common, central, forked air-inlet. V

4:. A tunnel oven having a series of narrow gas heating and a1r' heating regenerators distributed along the firing zone and arranged to feed to series of alternate gas and air inlets in the oven disposed suiiiciently closely together to produce a practically uninterrupted strip of flame, without requiring-a system of gas and air distributing ducts above the regenerators.

5. A tunnel oven as claimed in claim 4, wherein each regenerator has two discharge ducts leading to the oven chamber, crossed at their discharge ends so that the alternate air and gas inlets of the oven chamber are close together without the regenerators being excessively narrow.

' 6. A tunnel oven as claimed inclaim 1, with flues in the dividing walls of the regenerators for introducin rich gas into the oven when such gas is use lean gas, or with lean gas alternatively.

7. A tunnel oven as claimed in claim 1 hav-r ing below the regenerators distributing ducts whereby regenerators are connected in groups of two or more,said ducts being adapted for inlet and outlet of a gaseous medium alternately, or for outlet only.

8. A tunnel oven as claimed in claim 1, having below the regenerators distributing ducts whereby regenerators are connected in groups of two or more, said ducts being adapted for inlet and outlet of a gaseous medium alternately, or for outlet only, and dampers at the tops of the regenerators for controlling the flow therefrom to theinlets to the tunnel, and having dampers at the outlets of distributing ducts for separately regulating the feed to the regenerators of a group, whereby the flow through the regenerators maybe kept even.

9. A tunnel oven asclaimed in claim '1, with rich gas flues in the dividing walls of the regenerators for introducing rich fuel gas into the oven when such'gas is used as an alternative for lean gas, or with lean gas,

and in which an air inlet damper is provided for said flues and the outlets for the rich gas flues are in recesses in the wall of the oven chamber adjacent the regenerator air inlets,

so that by opening thedampers for admitting air, when a change over to lean gas is made,

graphite deposited in the rich gas flues can be burnt and the products of combustion can preheating air and gas for combustion distributed 1n pairs along the firing zone,the said regenerators feedlng an and gas to an and gas inlets alternating with each other along the tunnel in such manner that a sheet or strip of flame is produced, regulatable as regards its local intensity. I

11. A tunnel oven as claimed in claim 7 with flues in the dividing walls of the regenerators for introducing rich gas into the oven when such gas is used as an alternative for 7 e5 lean gas, or with lean gas alternatively.

12. A tunnel oven as claimed in claim 10,

with flues in the dividing walls of the regenerators for introducing rich gas into the oven when such gas is used as an alternative'for lean gas, or with lean as alternatively.

In witness whereof? afiix'my signature.

JOSEPH DANIELS.

as an alternative for abv 

